This research will gather physiological data to characterize sexual health in human beings. Quantification of multiple physiological variables during genital self-stimulation provides an objective description of the sexual response in men and women. General arousal variables, such as heart rate, electrocardiogram, respiratory flow rate and volume, skin conductance, electromyogram and blood pressure, are measured by conventional methods. Equipment has been specially designed to monitor changes in pelvic blood flow and muscle tension. Direct comparison of sexual responses in men and women is obtained using a rectal probe. Electrical signals are processed by a polygraph for immediate visual interpretation and simultaneously converted from analog to digital form by an on-line digital computer for storage and analysis. This sophisticated method obviates manual methods of extracting data from the original strip-chart record. Computer analysis capabilities permit immediate statistical manipulations and display of results on a digital plotter. This research also gathers extensive subjective information about sexual history and perceptions of sexual response during each session. Correlating experiential information with physiological data examines relationships between subjective report of sexual pleasure and magnitude of physiological changes. Using the same equipment and methods, the sexual responses will be monitored in individuals who are of different age groups, particularly the climacteric, and individuals with physical disabilities and sexual dysfunctions. This might determine what physiological and behavioral processes have been altered. Specific areas of applied research are biofeedback training of genital arousal, determining cardiac and metabolic expenditures of different sexual activities and screening for penile prosthesis surgery.